docs: remove @next [skip ci]

Author: haoqunjiang

Diff for: docs/migrations/migrate-from-v4.md

@@ -7,17 +7,17 @@ sidebar: auto
 First, install the latest Vue CLI globally:
 
 ```bash
-npm install -g @vue/cli@next
+npm install -g @vue/cli
 # OR
-yarn global add @vue/cli@next
+yarn global add @vue/cli
 ```
 
 ## Upgrade All Plugins at Once
 
 In your existing projects, run:
 
 ```bash
-vue upgrade --next
+vue upgrade
 ```
 
 And then follow the command line instructions.